Aria the Scarlet Ammo (Hidan no Aria) 9 (MF Bunko J) [Light Novel]

[Machine Translation] Tokyo Butei High School is a special school for training detectives who use military force, known as "Butei". Kinji Toyama, an ordinary person, is chosen as the partner of Aria, a super-elite and the strongest S-ranked detective in the Assault Department. Aria and Kinji are caught up in the conflict between the two federations - the "Division" and the "Family" - that began with the collapse of the criminal organization "Yi Wu". After the battle with Watson, Kinji is confronted by Riko, who has turned to Hilda's side. Will Kinji's call reach the heart of Riko, who is being toyed with by Hilda? The festival goes on peacefully, but a great terror looms. This is the ninth installment of a large scale action and romantic comedy.

東京武偵高校、そこは武力を行使する探偵―通称『武偵』を育成する特殊な学校。強襲科の超エリートでSランクの最強武偵・アリアのパートナーに選ばれてしまった(普段は)ただの一般人・遠山キンジ。犯罪組織『イ・ウー』の崩壊により始まった二つの連盟―『師団』と『眷属』の争いに巻き込まれたアリアとキンジ。ワトソンとの戦いを終えたキンジの前に現れたのは、ヒルダ側に寝返った理子だった。ヒルダにもてあそばれる理子の心にキンジの呼びかけは届くのか!?穏やかに進む文化祭、そして迫り来る大いなる恐怖―。大スケールアクション&ラブコメディー第9弾。